Balanced antenna system



. A. PRESS BALXiOBQAN'rENNA SYSTEM Filed June 17. 1920 iNVENTOR wnmzssss: 1 Abraham Pre $5 v BY (15 WM ATTORNEY Patented Jan. 13, 1925.

UNITED STATES PATENT OFFICE.

ABRAHAM PRESS, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC 80 MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

BALANCED ANTENNA SYSTEM.

Application filed June 17, 1920. Serial No. 389,539.

To all whom it may concern:

Be it known that l, ABRAHAM Pnnss, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and btate of rennsylvania, have invented a new and useful improvement in Balanced Antenna Systems, or which the following is a specification.

This invention relates to wireless telegraphic transmission systems and more especially to such systems in which a balanced antenna is employed.

An object of the present invention is to overcome the large amount of joulean waste in the ground wire at the bottom of the usual antenna constructions.

A further object of the invention is to do away, as far as possible, with all ground currents. HeretoIore, this has not been possible because of the asymmetrical nature of ordinary grounded aerials.

Other objects will make themselves manifest by an inspection of the drawings, when taken in con unction with the accompanying description and will be more particularly pointed out in the claims.

Fig. 1 is a diagrammatic View of my invention as applied to a sending station; Fig. 2 is a similar view of my invention as applied to a receiver station.

An overhead antenna 1 is connected to a coupling coil 2 by means of an adjustable connection 3, whereas an underground antenna 4, preferably of the nature of a counterpoise antenna, is connected to the same coupling coil 2 by means of an adjust-- able connection 5. An adjustable ground wire 6 is also connected to the coupling coil in such a manner as to give no current reading on the ammeter 7, with the ground switch 8 closed when power is fed to the driver connections 9 and 10. For zero-current reading in the ammeter 7 the two antennas will have substantially the same wave length. However, for certain types of static absolute equivalence in wave length is undesirable and therefore a true zero reading would not be preferable.

With the ground wire 6 properly adjusted, the electrostatic lines of force will necessarily pass according to my invention, from the overhead antenna 1 to the underground antenna 4, making the earths surface a surface of zero potential. It being a well known fact that electric waves pass, even with the asymmetric antenna systems common to the art, both over and under the earths surface, it will follow from the system above contemplated that the electricwave front must now be substantially perpendicular to the earths surface. Accordingly, there can be very little, if any, component of current parallel to the earths surface. However, I do not wish to be understood as limiting my invention to any particular working theory of operation.

In Fig. 2, I provide an adjustable trans-- former coil 11 to be fed by the signal" currents received by means of the underground antenna 4. Such coil, therefore, is connected across the coupling 2 by means of the ground wire 6 and the lead 12. On the other hand, a second adjustable transformer coil 13 is fed from the overground antenna circuit and is, therefore, connected by means of a lead 6 connected to the previously mentioned ground wire 6, and a lead 14 adjustably connected to the coupling coil nearest to the overground antenna. The two coils 11 and 13 co-act upon a secondary coil 15, feeding a receiver circuit having in series a detector 16 and a telephone set 17.

In the operation of the receiving system indicated in Fig. 2,: it will be seen that the signals received on the two antenna systems may be made to act additively, with emphasis upon the received signal current common to the two antennas. By such an arrangements of circuits, therefore, the elimination of static may be said to be achieved. This achievement will be still further emphasized when signals are sent out by means of similarly arranged overhead and underground antennas, as diagrammatically indicated in Fig. 1. The two embodiments of my invention, as applied, therefore, to a sending as well as to a receiving station, co-operatc to reduce static disturbances. It should be stated that the system of Fig. 2 is not limited to any particular form of sending system but will be found to act as a static eliminator with practically all types of sending systems, especially with the grounding switch 8 closed.

Having disclosed the nature of my invention, what I claim is:

1. In radio signalling, the method of avoiding disturbances from static which consists in sending radiations of opposite character over-ground and under-ground,

balancing said radiations, determining the existence of the balanced condition and disconnecting the determining instrument.

2. The method of signaling by radio energy which consists in exchanging energy with radiations above ground, exchanging energy with radiations below ground, conducting the difi'erence of said exchanged energy to ground and at times interrupting said conduction.

3. A grounded antenna system comprising an overground antenna and an underground antenna and means for so adjusting the system as to balance out the resultant current to ground.

4. A grounded antenna system comprising an overhead antenna and an underground antenna and switching means for connecting or disconnecting the antenna system from ground.

5. In combination with an ungrounded antenna system comprising an overhead antenna and an underground antenna, a receiver means and means for impressing upon said receiver means the impulses received from said ungrounded antenna system.

6. In combination with an ungrounded antenna system comprising an overhead antenna and an underground antenna, a driver means and means for impressing upon said antenna system the energy of said driver means.

7. The method of eliminating static comprising sending balanced signals of opposite character over-ground and under-ground, receiving the over-ground signals above ground, receiving the underground signals below ground, and conducting the received signals to ground.

8. The method of eliminating static comprising sending signals of opposite character over-ground and under-ground, so adjusting the energy of said signals that the overground energy nearly balances the underground energy, receiving the over-ground energy above ground, receiving the underground energy below ground, and conductively delivering the resultant of the two received energies to ground.

9. The method of exchanging energy between a radiating system and radiation which comprises delivering a supply of energy to the radiating system above ground, delivering a supply of energy to the radiating system below ground, at times conducting the non-radiated resultant energy to ground, adjusting the radiating system until said resultant is small, and at times stopping the conduction to ground.

10. The method of eliminating static comprising sending signals of opposite character over-ground and under-ground, preventing the conduction of said signals to ground at the sending point, receiving the over-ground signals above ground, receiving the under-ground signals below ground, adjusting the energy of the signals at the sending point until the signals nearly balance, adjusting the reception at the receiving point until the energy of the signals re ceived above ground nearly balances the energy of the signals received below ground, and conducting the small resultant energy to ground at the receiving point.

In testimony whereof I have hereunto subscribed my name this 12th day of June ABRAHAM PRESS. 

